VHF channels

The open VHF frequencies are intended for operational messaging , so it’s OK to share weather info, but not to talk sports. End each transmission with “over” and when you are done with the conversation say your boat name and out, “Big Daddy out,” which let’s everyone know you are done using that channel.

Data can be transmitted using the VHF radio signals that form the basis for the Forest Serviceʼs radio networks . Figure 1—Data is transmitted from a remote site by a modem (left), inter- face (center), and Bendix-King radio (right).

You are encouraged to check your VHF radio by calling the station in your area . When you transmit on its channel, you will hear a recorded response and then hear a playback of your voice verifying that your radio is transmitting, modulating and receiving.

The main purpose of a VHF antenna is to provide a radiator for the power that the transmitter in the radio produces and to radiate this energy in the correct direction .

To use your VHF, turn it on and pick a channel, set the squelch to the point where you don’t hear any white noise, and begin talking . Things to remember when you are on the radio: Monitor channel 16 when you are not actively in conversation with someone else.

VHF radio waves propagate mainly by line-of-sight , so they are blocked by hills and mountains, although due to refraction they can travel somewhat beyond the visual horizon out to about 160 km (100 miles).